Xenakis: Horos

Horos (1986): Monumental orchestra piece reknown in Xenakis theory circles as being the first extensive usage of cellular automata. According to Makis Solomos, the opening harmonies derive from self-developing algorithms taken directly from an issue of Scientific American and used on Xenakis' hand computer - the strange numbering at m. 10 (4200410) is an example of this. The work is massive as befits its title - horos = landmark - and its focus is with rare exception on harmony. I'm not sure again if it can be called harmony becuase for the most part the entire chromatic gamut is in play often in varying registrations - this is almsot an organ piece in its orchestration. So the strings play shifting colors of the chromatic complement over which the winds play the chromatic complement at a different speed with interjections from the brass - the entire pitch spectrum is so saturated that we don't hear it as such. Only when the winds come in with a high Lutoslawski-esque usage of a pelog-like scale do we get a reprieve before it happens again. By the end of the piece - a massive solid sonority with quicker interjections by various groups at quarter = 15 - we feel like we are hearing the whole spectrum when I don't believe we are. This is perhaps the most Messiaen-ic of the Xenakis works I've heard until now and seems to be pointing in a different direction - though its my belief that Xenakis didn't use the automata very much more owing to the difficulty of calculating out the pitches.